The present invention relates generally to a technology of maintaining an operating a subscriber transmission device (an access node or an access network) connected to a local exchange and incorporating a function of a geographical accommodation area of a subscriber (a subscriber terminal device) managed by this local exchange, and more particularly to a subscriber testing system capable of executing a subscriber test for the subscriber including a subscriber circuit disposed in the access node and a subscriber""s line accommodated in the subscriber circuit by making use of a V5 (V5.1, V5.2) interface protocol of a standardization communication protocol.
There is known a switching technology by which a remote device called an access node located far away from a local exchange, accommodates a subscriber line accommodated in the local exchange with a difficulty in terms of distance. The geographical accommodation area of the subscriber managed by the local exchange can be extended by providing the access node.
The same vendor has been developing and providing so far the access node as the remote device with respect to the local exchange on the basis its own specifications. Over the recent years, however, there have been promoted operations for standardizing processing functions of the local exchange and of the access node, and also the communication protocols for defining the communications therebetween. A V5 system (V5 interface protocol) standardized by ITU-T (International Telecommunications Union Telecommunication standardization sector), is known as its typical example.
The standardization in this category enables the local exchange and the access node to be purchased separately, and equipment makers (vendors) to be selected. Further, the common carriers expect that a reduction in costs for investment of the equipment is attained by improving a diversity of the existing devices.
Hence, according to the V5 system, there increased a possibility in which the access node and the local exchange are provided by the equipment makers different from each other.
In the case of using the V5 system described above, when maintaining and operating the local exchange and the access node, especially performing a subscriber test, it is required that the local exchange and the access node be operated in linkage. It is, however, a real situation that the maintenance and operation of the common carriers are based mainly on the local exchange in geometry. Therefore, actualization of the maintenance-and-operation linkage between the access node and the local exchange provided by the different equipment makers, needs a protocol conversion for connecting the local exchange and the access node and also a database for converting subscriber management data. It is therefore inevitable that the software and the added devices are required to be developed.
It follows that a merit of using the V5 system in which the call processing is standardized is decreased by half.
It is a primary object of the present invention to provide a subscriber testing system capable of performing a subscriber test of a subscriber including a subscriber circuit disposed in an access node and a subscriber""s line accommodated in the subscriber circuit by making use of a V5 interface protocol (V5 system) in the standardization communication protocol.
To accomplish the above object, according to one aspect of the present invention, a subscriber testing system comprises a switch accommodating a subscriber and having a maintenance/operation terminal and a communication node connected at a far distance to the switch via a logical link in which a communication protocol is defined, having a function of extending a geographical accommodation area of the subscriber that is managed by the switch, and including a testing device for executing a test for a subscriber""s line and subscriber circuit that correspond to the subscriber accommodated therein. In this system, a V5 interface protocol is used as the communication protocol. The switch includes a processing unit for transmitting to the communication node a piece of test specifying information, inputted from the maintenance/operation terminal, for indicating a subscriber test for the subscriber""s line and subscriber circuit that correspond to the accommodated subscriber by use of specifying information of a message type based on the V5 interface protocol. The communication node includes a processing unit for making the testing device execute the subscriber test on the basis of the test specifying information received via the logical link from the switch, and sending test result information for informing of a result of the test back to the switch by use of specifying information of a message type based on the V5 interface protocol.
In this architecture, any one of a port control protocol and a PSTN signal protocol of the V5 interface protocol may be used.
Further, when the accommodated subscriber is an analog subscriber, the PSTN signal protocol may be used.
When the accommodated subscriber is a digital subscriber, the port control protocol may be used.
Moreover, a field of an information element subsequent to a field of a message type in the V5 interface protocol may be used for specifying a test type of the subscriber test.
According to the present invention, the subscriber test of the subscriber including the subscriber circuit disposed in the access node and the subscriber""s line accommodated in the subscriber circuit, can be conducted by making use of the V5 system (V5.1, V5.2 interface protocols) in the standardization communication protocol. It is therefore possible to remarkably reduce the costs for developing the software and added devices, these developments being required as there arise necessities for a protocol conversion for connecting the access node and the local exchange and a database for converting the subscriber management data.
This makes it feasible to separately purchase the local exchange and the access node, which is a fundamental merit of using the V5 system in which the call processing is standardized. This also enables equipment makers to be selected and further a diversity of the existing devices to be improved. Then, this leads to actualization of a reduction in costs for investment of the equipment as the common carriers desire.